Display apparatus and method of manufacturing the same

ABSTRACT

A method of manufacturing a display apparatus that is capable of reducing manufacturing costs and a defect rate during manufacturing, and a display apparatus. The method includes forming a plurality of display units over a mother substrate; attaching a temporary protective film to a lower surface of the mother substrate; cutting the mother substrate and the temporary protective film along a periphery of each of the plurality of display units to obtain a plurality of display panels, each including a first area, a second area, and a bent area between the first area and the second area; removing the temporary protective film from the plurality of display panels; and attaching a lower protective film to a lower surface of each of the plurality of display panels so as to correspond to the first area in each display panel.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.15/417,000, filed Jan. 26, 2017, which claims priority to and thebenefit of Korean Patent Application No. 10-2016-0029696, filed Mar. 11,2016, the entire content of both of which is incorporated herein byreference.

BACKGROUND 1. Field

One or more aspects of example embodiments of the present disclosure arerelated to a display apparatus and a method of manufacturing the displayapparatus, and more particularly, to a method of manufacturing a displayapparatus that may be capable of reducing manufacturing costs and defectrate (e.g., the ratio of defective units) during manufacturing, and adisplay apparatus.

2. Description of the Related Art

In general, a display apparatus includes a display unit on a substrate.In such a display apparatus, at least a part of the display apparatusmay be bent so as to improve visibility at one or more angles or toreduce the area of the non-display area.

However, defects may occur and/or the lifespan of the display apparatusmay be reduced in a bendable display apparatus manufactured according tomethods in the related art.

SUMMARY

One or more aspects of example embodiments of the present disclosure aredirected toward a method of manufacturing a display apparatus that iscapable of reducing manufacturing costs and defect rate (e.g., the ratioof defective units) during manufacturing, and a display apparatus.

Additional aspects will be set forth in part in the description whichfollows and, in part, will be apparent from the description, or may belearned by practice of the presented embodiments.

One or more example embodiments of the present disclosure provide amethod of manufacturing a display apparatus, the method including:forming a plurality of display units over a mother substrate; attachinga temporary protective film to a lower surface of the mother substrate;cutting the mother substrate and the temporary protective film along aperiphery of each of the plurality of display units to obtain aplurality of display panels, each display panel comprising a first area,a second area, and a bent area (e.g., bendable area) between the firstarea and the second area; removing the temporary protective film fromthe plurality of display panels; and attaching a lower protective filmto a lower surface of each of the plurality of display panels tocorrespond to the first area in each display panel.

The attaching of the lower protective film may include attaching thelower protective film having an area greater than an area of the firstarea to expose an exposed part of the lower protective film to outsideof the display panel. The method may further include removing theexposed part of the lower protective film. The method may furtherinclude removing the exposed part of the lower protective film byirradiating the lower protective film with a laser beam.

The method may further include bending the display panel in the bentarea around a bending axis that crosses a virtual straight lineconnecting a center of the first area and a center of the second area.

The first area in each of the plurality of display panels may include acorresponding one of the plurality of display units.

The forming of the plurality of display units may include forming themother substrate over a carrier substrate and forming the plurality ofdisplay units over the mother substrate. The method may further includeseparating the mother substrate from the carrier substrate, wherein theattaching the temporary protective film may include attaching thetemporary protective film to a lower surface of the mother substrate,from which the carrier substrate is separated.

The method may further include attaching a printed circuit board and/oran electronic chip to the second area in each of the plurality ofdisplay panels, before removing the temporary protective film. A lengthof the second area may be equal to a length of the printed circuit boardor the electronic chip along a direction crossing (e.g., perpendicularor normal to) a virtual straight line connecting a center of the firstarea to a center of the second area.

One or more example embodiments of the present disclosure provide amethod of manufacturing a display apparatus, the method including:preparing a substrate including a bent area between a first area and asecond area; attaching a temporary protective film to a lower surface ofthe substrate throughout the first area, the bent area, and the secondarea; removing the temporary protective film; and attaching a lowerprotective film to the lower surface of the substrate to correspond tothe first area.

The attaching of the lower protective film may include attaching thelower protective film having an area greater than an area of the firstarea to the lower surface of the substrate to expose an exposed part ofthe lower protective film to outside of the substrate. The method mayfurther include removing the exposed part of the lower protective film.The method may further include removing the exposed part of the lowerprotective film by irradiating the lower protective film with a laserbeam.

The method may further include bending the substrate around a bendingaxis in the bent area.

The method may further include forming a display unit over the substratein the first area.

The method may further include attaching a printed circuit board or anelectronic chip to the second area of the substrate, before removing thetemporary protective film. A length of the second area may be equal to alength of the printed circuit board or the electronic chip along adirection crossing (e.g., perpendicular or normal to) a virtual straightline connecting a center of the first area to a center of the secondarea.

One or more example embodiments of the present disclosure provide adisplay apparatus including: a substrate including a bent area between afirst area and a second area, the bent area being bent around a bendingaxis so that a lower surface of the substrate in the first area and thelower surface of the substrate in the second area at least partiallyface each other; a display unit over an upper surface of the substratein the first area; a lower protective film over the lower surface of thesubstrate in at least a part of the first area; and a support layerbetween the lower protective film in the first area and the lowersurface of the substrate in the second area.

The support layer may be adhered to the lower protective film in thefirst area and the lower surface of the substrate in the second area.

A distance between a first lower surface of the substrate in the firstarea where the support layer is located and a second lower surface ofthe substrate in the second area where the support layer is located maybe less than a maximum distance between facing portions of the substratein a part of the substrate between the first lower surface and thesecond lower surface.

A part of the upper surface of the substrate between a first uppersurface of the substrate where the support layer is located and a secondupper surface of the substrate where the support layer is located mayprotrude past a first virtual plane including the second upper surfaceof the substrate where the support layer is located within the secondarea, in a direction away from the display unit. Another part of theupper surface of the substrate between the first upper surface of thesubstrate where the support layer is located and the second uppersurface of the substrate where the support layer is located may protrudepast a second virtual plane including first upper surface of thesubstrate where the display unit is located, in a direction toward thedisplay unit.

A surface of the support layer directly facing the lower protective filmmay have an area that is different from an area of a surface of thesupport layer directly facing the substrate in the second area. Asurface of the support layer directly facing the lower protective filmmay have an area that is greater than an area of a surface of thesupport layer directly facing the substrate in the second area.

The display apparatus may further include: an electronic device on aportion of the second upper surface of the substrate within the secondarea of the substrate where the support layer is located; and areinforcing film over the second upper surface of the substrate adjacentto the electronic device. The reinforcing film may cover all (e.g.,substantially all) of an exposed part of the second upper surface aroundthe electronic device.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects will become apparent and more readilyappreciated from the following description of the example embodiments,taken in conjunction with the accompanying drawings in which:

FIGS. 1, 2 to 7, and 8 are respectively a plan view, cross-sectionalviews, and a perspective view schematically showing processes in amethod of manufacturing a display apparatus, according to an embodimentof the present disclosure;

FIGS. 9 and 10 are schematic plan views of a method of manufacturing adisplay apparatus, according to an embodiment of the present disclosure;

FIG. 11 is a schematic plan view of a process in a method ofmanufacturing a display apparatus, according to an embodiment of thepresent disclosure;

FIGS. 12 and 13 are schematic cross-sectional views of processes in amethod of manufacturing a display apparatus, according to an embodimentof the present disclosure;

FIG. 14 is a schematic cross-sectional view of a part of a displayapparatus according to an embodiment of the present disclosure;

FIG. 15 is a schematic cross-sectional view of a part of a displayapparatus according to an embodiment of the present disclosure;

FIG. 16 is a schematic cross-sectional view of a part of a displayapparatus according to an embodiment of the present disclosure;

FIG. 17 is a schematic cross-sectional view of a part of a displayapparatus according to an embodiment of the present disclosure; and

FIG. 18 is a schematic cross-sectional view of a part of a displayapparatus according to an embodiment of the present disclosure.

DETAILED DESCRIPTION

Reference will now be made in more detail to example embodiments,examples of which are illustrated in the accompanying drawings, whereinlike reference numerals refer to like elements throughout andduplicative descriptions thereof may not be provided. In this regard,the present embodiments may have different forms and should not beconstrued as being limited to the descriptions set forth herein.Accordingly, the embodiments are merely described below, by referring tothe drawings, to explain aspects of the present description. As usedherein, the term “and/or” includes any and all combinations of one ormore of the associated listed items. Expressions such as “at least oneof”, “one of”, and “selected from”, when preceding a list of elements,modify the entire list of elements and do not modify the individualelements of the list.

Hereinafter, the present disclosure will be described in detail byexplaining example embodiments of the present disclosure with referenceto the attached drawings.

The sizes and thicknesses of components (such as of layers, films,panels, regions, etc.) in the drawings may be exaggerated forconvenience of explanation. In other words, since sizes and thicknessesof components in the drawings are arbitrarily illustrated forconvenience of explanation, the following example embodiments are notlimited thereto.

It will be understood that when an element such as a layer, film,region, or substrate is referred to as being “on” or “over” anotherelement, it can be directly on the other element or interveningelement(s) may also be present. In contrast, when an element is referredto as being “directly on” another element, no intervening elements arepresent.

In the following examples, the x-axis, the y-axis, and the z-axis arenot limited to three axes of the rectangular (e.g., Cartesian)coordinate system, and may be interpreted in a broader sense. Forexample, the x-axis, the y-axis, and the z-axis may be perpendicular toone another, or may represent different directions that are notperpendicular to one another.

FIGS. 1, 2 to 7, and 8 are respectively a plan view, cross-sectionalviews, and a perspective view schematically showing processes in amethod of manufacturing a display apparatus, according to an embodimentof the present disclosure.

As shown in FIG. 1, a plurality of display units DU may be formed on amother substrate 100. Other processes may be performed prior to formingthe plurality of display units DU (such as a process of forming a bufferlayer on an entire surface of the mother substrate 100). In someembodiments, when the plurality of display units DU are formed,electronic devices (such as thin film transistors) that are electricallyconnected to display devices may be formed in addition to the displaydevices, and may be formed on a peripheral area that is outside of thedisplay area on which the display devices are located. In someembodiments, an encapsulation layer for protecting the display devicesmay be provided when the plurality of display units DU are formed.Detailed structures of the display units DU will be described later.

As described above, the mother substrate 100 (on which the plurality ofdisplay units DU are formed) may include one or more materials havingflexible or bendable characteristics, for example, polymer resins (suchas polyether sulfone (PES), polyacrylate, polyether imide (PEI),polyethylene naphthalate (PEN), polyethylene terephthalate (PET),polyphenylene sulfide (PPS), polyarylate (PAR), polyimide (PI),polycarbonate (PC), and/or cellulose acetate propionate (CAP)).

The plurality of display units DU shown in FIG. 1 are formed on themother substrate 100, which is on a carrier substrate 10, as shown inFIG. 2. The carrier substrate 10 may include, for example, glass of asufficient thickness. The carrier substrate 10 may have sufficient orsuitable hardness so as to prevent or reduce the mother substrate 100(which may include the flexible or bendable material) from being curvedor deformed during manufacturing. For example, the mother substrate 100may be formed on the carrier substrate 10 having sufficient or suitablehardness, and the plurality of display units DU may be formed on themother substrate 100.

After forming the display units DU as described above, the mothersubstrate 100 is separated from the carrier substrate 10. As shown inFIG. 3, a temporary protective film 20 is then attached to a lowersurface of the mother substrate 100 (e.g., the surface perpendicular ornormal to a −z direction). The temporary protective film 20 may preventor reduce the lower surface of the mother substrate 100 from beingdamaged during manufacturing. The temporary protective film 20 will beremoved during manufacturing, as will be described later, and thereforean adhesive force between the temporary protective film 20 and themother substrate 100 may not be strong. Accordingly, as will bedescribed later, an adhesive applied between the temporary protectivefilm 20 and the mother substrate 100 may not have a strong adhesiveforce.

After attaching the temporary protective film 20 to the lower surface ofthe mother substrate 100, the mother substrate 100 and the temporaryprotective film 20 are simultaneously cut (e.g., at the same time). Forexample, the mother substrate 100 and the temporary protective film 20are cut along a periphery of each of the plurality of display units DU,thereby yielding a plurality of display panels. The mother substrate 100and the temporary protective film 20 may be cut in one or more ways(e.g., the mother substrate 100 and the temporary protective film 20 maybe cut using a laser beam and/or a cutting wheel).

FIG. 5 is a schematic cross-sectional view of a part of one of aplurality of display panels obtained through the above processes. Asshown in FIG. 5, each of the plurality of display panels includes afirst area 1A, a second area 2A, and a bent area (e.g., bendable area)BA between the first area 1A and the second area 2A. Hereinafter, thesubstrate in each of the plurality of display panels will be denoted bythe same reference numeral as the mother substrate.

The first area 1A may include a display area DA. The first area 1A mayalso include part of a non-display area that is on an outer portion ofthe display area DA. The second area 2A may also include part of thenon-display area.

A display device 300 and a thin film transistor 210 (to which thedisplay device 300 is electrically connected) may be located on thedisplay area DA of the display panel. FIG. 5 shows that the displaydevice 300 includes an organic light-emitting device (OLED) on thedisplay area DA. Regarding the electric connection of the organiclight-emitting device to the thin film transistor 210, the pixelelectrode 310 (e.g., of the display device 300) is electricallyconnected to the thin film transistor 210. If necessary, a thin filmtransistor may be included in a peripheral area outside the display areaDA on the substrate 100. The thin film transistor located in theperipheral area may be part of a circuit unit for controlling electricsignals applied to the display area DA.

The thin film transistor 210 may include a semiconductor layer 211, agate electrode 213, a source electrode 215 a, and a drain electrode 215b, and the semiconductor layer 211 may include amorphous silicon,polycrystalline silicon, or an organic semiconductor material. A gateinsulating layer 120 may be between the semiconductor layer 211 and thegate electrode 213 in order to ensure insulation between thesemiconductor layer 211 and the gate electrode 213, and the gateinsulating layer 120 may include an inorganic material (such as siliconoxide, silicon nitride, and/or silicon oxynitride). In some embodiments,an interlayer insulating layer 130 may be on the gate electrode 213, andthe source electrode 215 a and the drain electrode 215 b may be on theinterlayer insulating layer 130, the interlayer insulating layer 130including an inorganic material (such as silicon oxide, silicon nitride,and/or silicon oxynitride). The insulating layers including theinorganic material as above may be formed by chemical vapor deposition(CVD) or atomic layer deposition (ALD). This may also be applied to oneor more embodiments that will be described later and modified examplesthereof.

A buffer layer 110 may be between the thin film transistor 210 havingthe above structure and the substrate 100, as described above. Thebuffer layer 110 may include an inorganic material (such as siliconoxide, silicon nitride, and/or silicon oxynitride). The buffer layer 110may improve the flatness of (e.g., planarize) an upper surface of thesubstrate 100, or may prevent or reduce infiltration of impurities fromthe substrate 100 into the semiconductor layer 211 of the thin filmtransistor 210.

In some embodiments, a planarization layer 140 may be over the thin filmtransistor 210. For example, as shown in FIG. 5, when an organiclight-emitting device is on the thin film transistor 210, theplanarization layer 140 may planarize an upper portion of a protectivelayer covering the thin film transistor 210. The planarization layer 140may include an organic material, e.g., acryl, benzocyclobutene (BCB),and/or hexamethyldisiloxane (HMDSO). In FIG. 5, the planarization layer140 has a single-layered structure, but may be modified in one or moresuitable embodiments. For example, the planarization layer 140 may havea multi-layered structure. In some embodiments, the planarization layer140 may have an opening near an outer portion of the display area DA sothat the region of the planarization layer 140 corresponding to thedisplay area DA and the region of the planarization layer 140corresponding to the second area 2A may be physically separated fromeach other. Thus, impurities from the outside may not reach the displayarea DA via the planarization layer 140.

In the display area DA, an organic light-emitting device may be on theplanarization layer 140, wherein the organic light-emitting deviceincludes a pixel electrode 310, an opposite electrode 330, and anintermediate layer 320 between the pixel electrode 310 and the oppositeelectrode 330 and including an emission layer. The pixel electrode 310may contact one of the source electrode 215 a and the drain electrode215 b via an opening in the planarization layer 140, as shown in FIG. 5,so as to be electrically connected to the thin film transistor 210.

A pixel defining layer 150 may be over the planarization layer 140. Thepixel defining layer 150 may have openings corresponding to the areas ofone or more sub-pixels, that is, openings exposing at least a centerportion of the pixel electrode 310, thereby defining the pixels. Also,in the embodiment of FIG. 5, the pixel defining layer 150 increases adistance between an edge of the pixel electrode 310 and an edge of theopposite electrode 330 over the pixel electrode 310, so as to prevent orreduce generation of an arc at the edge of the pixel electrode 310. Thepixel defining layer 150 may include, for example, an organic materialsuch as polyimide and/or HMDSO.

The intermediate layer 320 of the organic light-emitting device mayinclude low-molecular weight organic materials or polymer materials.When the intermediate layer 320 includes a low-molecular weight organicmaterial, the intermediate layer 320 may include a hole injection layer(HIL), a hole transport layer (HTL), an emission layer (EML), anelectron transport layer (ETL), and an electron injection layer (EIL) ina single or multiple-layered structure. Non-limiting examples of organicmaterials may include copper phthalocyanine (CuPc),N,N′-di(naphthalene-1-yl)-N,N′-diphenyl-benzidine (NPB), andtris-8-hydroxyquinoline aluminum (Alq₃). The low-molecular weightorganic materials may be deposited by a vacuum deposition method.

When the intermediate layer 320 includes a polymer material, theintermediate layer 320 may include an HTL and an EML. Here, the HTL mayinclude PEDOT, and the EML may include a poly-phenylene vinylene(PPV)-based or polyfluorene-based polymer material. The intermediatelayer 320 may be formed using a screen printing method, an inkjetprinting method, and/or a laser induced thermal imaging (LITI) method.

However, the intermediate layer 320 is not limited to the above example,and may have one or more suitable structures. In some embodiments, theintermediate layer 320 may include a layer that is integrally formedthroughout a plurality of pixel electrodes 310, or a layer that ispatterned to correspond to each of the plurality of pixel electrodes310.

The opposite electrode 330 is above the display area DA, and as shown inFIG. 5, may cover (e.g., substantially cover) the display area DA. Forexample, the opposite electrode 330 may be integrally formed withrespect to a plurality of organic light-emitting devices, so as tocorrespond to the plurality of pixel electrodes 310.

Since the organic light-emitting device may be easily damaged byexternal moisture or oxygen, an encapsulation layer 400 may cover andprotect the organic light-emitting device. The encapsulation layer 400covers the display area DA, and then may extend outside the display areaDA. The encapsulation layer 400 may include a first inorganicencapsulation layer 410, an organic encapsulation layer 420, and asecond inorganic encapsulation layer 430, as shown in FIG. 5.

The first inorganic encapsulation layer 410 covers the oppositeelectrode 330, and may include silicon oxide, silicon nitride, and/orsilicon oxynitride. If necessary, other layers (such as a capping layer)may be between the first inorganic encapsulation layer 410 and theopposite electrode 330. Since the first inorganic encapsulation layer410 is formed according to a structure thereunder, the first inorganicencapsulation layer 410 may have an uneven upper surface, as shown inFIG. 5. The organic encapsulation layer 420 may cover the firstinorganic encapsulation layer 410, and unlike the first inorganicencapsulation layer 410, the organic encapsulation layer 420 may have aneven upper surface. In more detail, the organic encapsulation layer 420may have a roughly even upper surface at a portion corresponding to thedisplay area DA. The organic encapsulation layer 420 may include atleast one material selected from polyethylene terephthalate,polyethylene naphthalate, polycarbonate, polyimide, polyethylenesulfonate, polyoxymethylene, polyarylate, and hexamethyldisiloxane. Thesecond inorganic encapsulation layer 430 covers the organicencapsulation layer 420, and may include silicon oxide, silicon nitride,and/or silicon oxynitride. The second inorganic encapsulation layer 430may contact the first inorganic encapsulation layer 410 at an edgethereof at an outer portion of the display area DA, in order not toexpose the organic encapsulation layer 420 to the outside.

As described above, when the encapsulation layer 400 includes the firstinorganic encapsulation layer 410, the organic encapsulation layer 420,and the second inorganic encapsulation layer 430, even if a crack occursin the encapsulation layer 400 having the above multi-layered structure,the crack may be disconnected (e.g., disjoint) between the firstinorganic encapsulation layer 410 and the organic encapsulation layer420 or between the organic encapsulation layer 420 and the secondinorganic encapsulation layer 430. As such, formation of a path throughwhich external moisture or oxygen may infiltrate into the display areaDA may be prevented or reduced.

After the plurality of display panels having the above structures isobtained, elements may be formed on each of the plurality of displaypanels. For example, a polarization plate 520 may be attached to theencapsulation layer 400 via an optically clear adhesive (OCA) 510. Thepolarization plate 520 may reduce reflection of external light. Forexample, when external light passes through the polarization plate 520,is reflected by an upper surface of the opposite electrode 330, and thenpasses through the polarization plate 520 again, the external lightpasses through the polarization plate 520 twice and a phase of theexternal light may be thereby changed. When the phase of reflected lightis different from the phase of the external light originally enteringthe polarization plate 520, destructive interference occurs, andaccordingly, the reflection of the external light may be reduced andvisibility may be improved. The OCA 510 and the polarization plate 520may cover an opening in the planarization layer 140 as shown in FIG. 5.

The method of manufacturing the display apparatus according toembodiments of the present disclosure may not include the process offorming the polarization plate 520, and in some embodiments, thepolarization plate 520 may not be provided or may be replaced withanother component. For example, the polarization plate 520 may not beprovided, and instead, a black matrix and a color filter may be formedto reduce the reflection of external light in the display apparatusmanufactured by the method.

After that, as shown in FIG. 6, the temporary protective film 20 isremoved from the plurality of display panels. In some embodiments, asshown in FIG. 7, a lower protective film 170 is attached to a lowersurface (e.g., the surface perpendicular or normal to a −z direction) ofeach of the display panels so as to correspond to the first area 1A ineach of the plurality of display panels.

The lower protective film 170 covers (e.g., substantially covers) mostof the first area 1A of the display panel, as shown in FIG. 7. In someembodiments, the lower protective film 170 does not cover the bent areaBA and the second area 2A of the display panel. As shown in FIG. 7, anedge of the lower protective film 170 facing toward the second area 2Amay be within the first area 1A so as not to overlap with the bent areaBA, and moreover, not to contact the bent area BA. Here, even when theedge of the lower protective film 170 facing toward the second area 2Ais within the first area 1A, the edge may slightly vertically overlapwith a part of an organic material layer 160, which may have an unevensurface 160 a, as shown in FIG. 7. This is because the lower protectivefilm 170 covers as much of the lower surface of the display panel aspossible to protect a large part of the display panel. The lowerprotective film 170 protects the lower surface of the display panel, forexample, a lower surface of the substrate 100 (e.g., the surfaceperpendicular or normal to a −z direction), and to do this, the lowerprotective film 170 may have a sufficient or suitable level of hardness.For example, the lower protective film 170 may include polyethyleneterephthalate (PET).

Since the lower protective film 170 protects the lower surface of thesubstrate 100, the lower protective film 170 does not need to be easilyremoved during handling. Therefore, an adhesive force between the lowerprotective film 170 and the substrate 100 may be maintained at asufficiently or suitably strong degree. To do this, the adhesive betweenthe lower protective film 170 and the substrate 100 needs to have asufficiently strong adhesive force. As described above, the adhesiveforce between the temporary protective film 20 and the substrate 100 maynot be strong. Accordingly, the adhesive force between the lowerprotective film 170 and the substrate 100 may be greater than thatbetween the temporary protective film 20 and the mother substrate 100.

When a film is attached to a substrate by an adhesive, an ultra-violet(UV) curable adhesive may be used, and the UV curable adhesive may beirradiated with a suitable amount of UV light in order to adjust theadhesive force of the adhesive. Here, the adhesive force of the adhesivemay be controlled by adjusting the time period of UV light exposure orthe intensity of the UV light. Therefore, the time period of UV lightexposure of the adhesive between the temporary protective film 20 andthe mother substrate 100 may be longer than that of the adhesive betweenthe lower protective film 170 and the substrate 100, and thus, theadhesive force between the lower protective film 170 and the substrate100 may be greater than that between the temporary protective film 20and the mother substrate 100. In another embodiment, the intensity ofthe UV light irradiated onto the adhesive between the temporaryprotective film 20 and the mother substrate 100 may be greater than theintensity of the UV light irradiated onto the adhesive between the lowerprotective film 170 and the substrate 100, and thus, the adhesive forcebetween the lower protective film 170 and the substrate 100 may begreater than that between the temporary protective film 20 and themother substrate 100.

When the coverage ratio of the adhesive between the lower protectivefilm 170 and the substrate 100 on the substrate 100 is greater than thecoverage ratio of the adhesive between the temporary protective film 20and the mother substrate 100 on the mother substrate 100, the totaladhesive force between the lower protective film 170 and the substrate100 may be greater than the total adhesive force between the temporaryprotective film 20 and the mother substrate 100. In this case, it isassumed that the adhesive between the temporary protective film 20 andthe mother substrate 100 is not applied to the entire area of the mothersubstrate 100 or the temporary protective film 20 (e.g., the coverageratio is less than 1).

As described above, after the lower protective film 170 is attached tothe substrate 100, the display panel may be bent as shown in FIG. 8.FIG. 8 only shows the substrate 100 for convenience of description. Thesubstrate 100 is bent at the bent area BA, and in particular, thesubstrate 100 is bent around a bending axis BAX that crosses a virtualline IL (see FIG. 9) that connects a center C1 of the first area 1A to acenter C2 of the second area 2A.

Here, since the lower protective film 170 corresponding to the firstarea 1A is not in the bent area BA as described above, the lowerprotective film 170 may not cause defects when the display panel isbent. Since the lower protective film 170 protects the lower surface ofthe substrate 100, the lower protective film 170 may have its ownhardness (e.g., may be rigid). Accordingly, if the lower protective film170 is also on the bent area BA, the lower protective film 170 may beseparated from the substrate 100 when the substrate 100 is bent becausethe lower protective film 170 has low flexibility. Alternatively, if thelower protective film 170 is on the bent area BA, defects such aswrinkles may occur on the lower protective film 170 in the bent area BAwhen the substrate 100 is bent. However, according to the method ofmanufacturing the display apparatus in embodiments of the presentdisclosure, since the lower protective film 170 is not within the bentarea BA, such defects may be prevented or reduced when bending thedisplay panel after attaching the lower protective film 170 to thedisplay panel.

The buffer layer 110, the gate insulating layer 120, and the interlayerinsulating layer 130 including the inorganic material may becollectively referred to as a first inorganic insulating layer. Thefirst inorganic insulating layer may have a first opening correspondingto the bent area BA, as shown in FIGS. 5 to 7. For example, the bufferlayer 110, the gate insulating layer 120, and the interlayer insulatinglayer 130 may respectively have openings 110 a, 120 a, and 130 acorresponding to the bent area BA. The phrase “the first openingcorresponds to the bent area BA” may denote that the first openingoverlaps with the bent area BA. In some embodiments, the area of thefirst opening may be greater than that of the bent area BA. For example,in FIGS. 5 to 7, a width OW of the first opening is greater than a widthof the bent area BA. Here, the area of the first opening may be definedas the smallest area among the openings 110 a, 120 a, and 130 a of thebuffer layer 110, the gate insulating layer 120 and the interlayerinsulating layer 130. In some embodiments, in FIGS. 5 to 7, the area ofthe first opening may be defined by an area of the opening 110 a in thebuffer layer 110.

In FIGS. 5 to 7, an inner side surface of the opening 110 a of thebuffer layer 110 and an inner side surface of the opening 120 a in thegate insulating layer 120 correspond to each other, but embodiments ofthe present disclosure are not limited thereto. For example, an area ofthe opening 120 a of the gate insulating layer 120 may be greater thanan area of the opening 110 a in the buffer layer 110. In this case, thearea of the first opening may be defined as the smallest area among theopenings 110 a, 120 a, and 130 a of the buffer layer 110, the gateinsulating layer 120, and the interlayer insulating layer 130.

When the plurality of display units DU are formed as described above,the organic material layer 160 may be formed to at least partially fillthe first opening in the first inorganic insulating layer. In FIGS. 5 to7, the organic material layer 160 completely fills the first opening,and the display unit DU includes a first conductive layer 215 c thatextends from the first area 1A toward the second area 2A through thebent area BA, located on the organic material layer 160. The firstconductive layer 215 c may be on an inorganic insulating layer (such asthe interlayer insulating layer 130) where there is no organic materiallayer 160. The first conductive layer 215 c may be formed simultaneouslywith (e.g., at the same time as) the source electrode 215 a or the drainelectrode 215 b using the same material as the source electrode 215 a orthe drain electrode 215 b.

As described above, after the lower protective film 170 is attached tothe lower surface of the substrate 100, as shown in FIG. 7, the displaypanel may be bent at the bent area BA, as shown in FIG. 8. Here, tensilestress may be applied to the first conductive layer 215 c while thesubstrate 100 is bent at the bent area BA, but the method ofmanufacturing the display apparatus according to the embodiment of thepresent disclosure may prevent or reduce the occurrence of defects inthe first conductive layer 215 c during the bending process.

If the first inorganic insulating layer including the buffer layer 110,the gate insulating layer 120, and/or the interlayer insulating layer130 does not include an opening at the bent area BA, but is formedcontinuously from the first area 1A to the second area 2A, and if thefirst conductive layer 215 c is on the first inorganic insulating layer,a large tensile stress may be applied to the first conductive layer 215c when the substrate 100 is bent. For example, if the first inorganicinsulating layer has a higher hardness than the organic material layer,cracks are more likely to occur in the first inorganic insulating layerat the bent area BA. If a crack occurs in the first inorganic insulatinglayer, the first conductive layer 215 c on the first inorganicinsulating layer may also have a crack, and thus, there is a highpossibility of generating a defect such as a disconnection in the firstconductive layer 215 c.

However, in the method of manufacturing the display apparatus accordingto embodiments of the present disclosure, the first inorganic insulatinglayer has the first opening at the bent area BA (as described above),and the part of the first conductive layer 215 c corresponding to thebent area BA is on the organic material layer 160, which fills at leasta part of the first inorganic insulating layer. Since the firstinorganic insulating layer has the first opening at the bent area BA,the possibility of generating a crack in the first inorganic insulatinglayer is low, and the possibility of generating a crack in the organicmaterial layer 160 is also low, due to the organic material content.Therefore, the occurrence of the crack in the part of the firstconductive layer 215 c corresponding to the bent area BA and located onthe organic material layer 160 may be prevented or reduced. Since theorganic material layer 160 has a hardness that is lower than that of theinorganic material layer, the tensile stress generated due to thebending of the substrate 100 may be absorbed by the organic materiallayer 160 so that concentration of the tensile stress onto the firstconductive layer 215 c may be effectively reduced.

In some embodiments, when the display unit DU is formed, secondconductive layers 213 a and 213 b, in addition to the first conductivelayer 215 c, may be formed. The second conductive layers 213 a and 213 bmay be on the first area 1A or the second area 2A at a different layerlevel from that of the first conductive layer 215 c, and may beelectrically connected to the first conductive layer 215 c. In FIGS. 5to 7, the second conductive layers 213 a and 213 b are located at thesame layer level as the gate electrode 213 of the thin film transistor210, for example, on the gate insulating layer 120, and may include thesame material as the gate electrode 213. In some embodiments, the firstconductive layer 215 c contacts the second conductive layers 213 a and213 b via contact holes formed in the interlayer insulating layer 130.In some embodiments, the second conductive layer 213 a is located abovethe first area 1A, and the second conductive layer 213 b is locatedabove the second area 2A.

The second conductive layer 213 a located over the first area 1A may beelectrically connected to the thin film transistor 210 in the displayarea DA, and accordingly, the first conductive layer 215 c may beelectrically connected to the thin film transistor 210 in the displayarea DA via the second conductive layer 213 a. The second conductivelayer 213 b located in the second area 2A may be electrically connectedto the thin film transistor 210 in the display area DA via the firstconductive layer 215 c, as well. As described above, the secondconductive layers 213 a and 213 b on the outer portion of the displayarea DA may be electrically connected to components in the display areaDA, and/or may extend toward the display area DA and be at leastpartially in the display area DA.

As described above, after the lower protective film 170 is attached tothe lower surface of the substrate 100, as shown in FIG. 7, the displaypanel is bent at the bent area BA, as shown in FIG. 8. Here, tensilestress may be applied to the elements within the bent area BA when thesubstrate 100 is bent at the bent area BA.

Therefore, the first conductive layer 215 c that extends across the bentarea BA may include a material having a high elongation rate, and thus,the occurrence of cracks in the first conductive layer 215 c and/or adefect such as a disconnection in the first conductive layer 215 c maybe prevented or reduced. In some embodiments, the second conductivelayers 213 a and 213 b may include a material having a lower elongationrate than that of the first conductive layer 215 c, and/orelectrical/physical characteristics different from those of the firstconductive layer 215 c on the first area 1A or the second area 2A, andthus, the efficiency of transferring electrical signals in the displayapparatus may be improved and/or a defect rate (e.g., the ratio ofdefective units) during manufacturing may be reduced. For example, thesecond conductive layers 213 a and 213 b may include molybdenum, and thefirst conductive layer 215 c may include aluminum. In some embodiments,the first conductive layer 215 c and the second conductive layers 213 aand 213 b may include multi-layered structures.

In some embodiments unlike the examples shown in FIGS. 5 to 7, an uppersurface of the second conductive layer 213 b located in the second area2A may not be covered by the planarization layer 140, but may be exposedto the outside so as to be electrically connected to one or moreelectronic devices or printed circuit boards.

In some embodiments, as shown in FIGS. 5 to 7, the organic materiallayer 160 may have an uneven surface 160 a in at least a part of anupper surface thereof (e.g., the surface perpendicular or normal to +zdirection). When the organic material layer 160 has the uneven surface160 a, the first conductive layer 215 c located on the organic materiallayer 160 may have an upper surface and/or a lower surface having ashape corresponding to the uneven surface 160 a of the organic materiallayer 160.

As described above, since tensile stress may be applied to the firstconductive layer 215 c when the substrate 100 is bent at the bent areaBA during manufacturing of the display apparatus, when the upper surfaceand/or the lower surface of the first conductive layer 215 c has a shapecorresponding to the uneven surface 160 a of the organic material layer160, the amount of tensile stress applied to the first conductive layer215 c may be reduced. For example, the tensile stress that may begenerated during the bending process may be reduced through deformationof the organic material layer 160 having a relatively low strength, andthe first conductive layer 215 c having an uneven shape before thebending process may be transformed to correspond to the shape of theorganic material layer 160, which is deformed due to the bendingprocess, and thus, the occurrence of defects (such as disconnection inthe first conductive layer 215 c) may be prevented or reduced.

The uneven surface 160 a may be formed at least partially in the uppersurface of the organic material layer 160 (e.g., the surfaceperpendicular or normal to the +z direction), and a surface area of theupper surface of the organic material layer 160 and a surface area ofthe upper and lower surfaces of the first conductive layer 215 c in thefirst opening may be increased. A large surface area on the uppersurface of the organic material layer 160 and the upper and lowersurfaces of the first conductive layer 215 c may be associated with alarge deformation margin in order to reduce the tensile stress causedupon bending of the substrate 100.

When the first conductive layer 215 c is located on the organic materiallayer 160, the lower surface of the first conductive layer 215 c has ashape corresponding to the uneven surface 160 a of the organic materiallayer 160. However, in some embodiments the upper surface of the firstconductive layer 215 c may have an uneven surface that is independentfrom the shape of the uneven surface 160 a of the organic material layer160.

The uneven surface 160 a in the upper surface of the organic materiallayer 160 (e.g., the surface perpendicular or normal to the +zdirection) may be formed in one or more suitable ways. For example, aphotoresist material may be used to form the organic material layer 160,and the amount of photo exposure may be varied across the organicmaterial layer 160 (the upper surface of which is flat) using a slitmask or a half-tone mask, such that a certain portion(s) may be etched(removed) more than other portions. In some embodiments, the depressedportion in the upper surface of the organic material layer 160 may beetched more than other portions. However, the method of manufacturingthe display apparatus according to embodiments of the present disclosureis not limited to the above example. For example, after forming theorganic material layer 160 having a flat upper surface, certain portionsmay be removed by a dry etching method, and other suitable methods maybe used.

In order for the organic material layer 160 to have the uneven surface160 a on the upper surface thereof (e.g., the surface perpendicular ornormal to the +z direction), the organic material layer 160 may includea plurality of grooves in the upper surface thereof (e.g., the surfaceperpendicular or normal to the +z direction), wherein the plurality ofgrooves extend in a first direction (e.g., along the +y direction).Here, the shape of the upper surface of the first conductive layer 215 con the organic material layer 160 corresponds to the shape of the uppersurface of the organic material layer 160.

The organic material layer 160 may have the uneven surface 160 a onlywithin the first opening of the first inorganic insulating layer. InFIGS. 5 to 7, a width UEW of the uneven surface 160 a of the organicmaterial layer 160 is less than a width OW of the first opening of thefirst inorganic insulating layer. When the organic material layer 160has the uneven surface 160 a within as well as around the first openingin the first inorganic insulating layer, the uneven surface 160 a isnear the internal surface of the opening 110 a in the buffer layer 110,the internal surface of the opening 120 a in the gate insulating layer120, and/or the internal surface of the opening 130 a in the interlayerinsulating layer 130. The organic material layer 160 has a smallerthickness on the depressed portion than on the protruding portions ofthe uneven surface 160 a (e.g., the uneven surface 160 a has thickerprotruding portions and thinner depressed portions), and thus, ifdepressed portions are around the internal surface of the opening 110 ain the buffer layer 110, the internal surface of the opening 120 a inthe gate insulating layer 120, and/or the internal surface of theopening 130 a in the interlayer insulating layer 130, the organicmaterial layer 160 may be disconnected. Therefore, when the organicmaterial layer 160 only has the uneven surface 160 a within the firstopening of the first inorganic insulating layer, the disconnection ofthe organic material layer 160 around the internal surface of theopening 110 a in the buffer layer 110, the internal surface of theopening 120 a of the gate insulating layer 120, and/or the internalsurface of the opening 130 a in the interlayer insulating layer 130 maybe prevented or reduced.

As described above, in order not to generate the disconnection in thefirst conductive layer 215 c at the bent area BA, the organic materiallayer 160 may have the uneven surface 160 a corresponding to the bentarea BA. Therefore, the area of the uneven surface 160 a of the organicmaterial layer 160 may be greater than that of the bent area BA and lessthan that of the first opening. For example, as shown in FIGS. 5 to 7,the width UEW of the uneven surface 160 a of the organic material layer160 is greater than the width of the bent area BA and less than thewidth OW of the first opening.

When one of the buffer layer 110, the gate insulating layer 120, and theinterlayer insulating layer 130 includes an organic insulating material,the organic material layer 160 may be formed simultaneously orconcurrently (e.g., at the same time) when the layer including theorganic insulating material is formed, and moreover, the layer includingthe organic insulating material and the organic material layer 160 maybe integrally formed with each other. Non-limiting examples of theorganic insulating material may include polyethylene terephthalate,polyethylene naphthalate, polycarbonate, polyimide, polyethylenesulfonate, polyoxymethylene, polyarylate, and hexamethyldisiloxane.

After obtaining the plurality of display panels as shown in FIG. 5, astress neutralization layer (SNL) 600 may be formed on an outer portionof the display area DA before removing the temporary protective film 20from each of the plurality of display panels, as shown in FIG. 6. Forexample, the SNL 600 may be located over the first conductive layer 215c to at least correspond to the bent area BA.

When a stack structure is bent, there is a stress neutral plane in thestack structure. If there is no SNL 600, when the substrate 100 is bent,excessive tensile stress may be applied to the first conductive layer215 c in the bent area BA, because the location of the first conductivelayer 215 c may not correspond to a stress neutral plane. However, byforming the SNL 600 and adjusting a thickness and a modulus of the SNL600, a location of the stress neutral plane in the structure includingthe substrate 100, the first conductive layer 215 c, and the SNL 600 maybe adjusted. Therefore, the stress neutral plane may be adjusted to belocated around the first conductive layer 215 c via the SNL 600, andthus, the tensile stress applied to the first conductive layer 215 c maybe reduced.

The SNL 600 may extend to an end of the substrate 100 in the displayapparatus, unlike the example of FIG. 2. For example, in the second area2A, the first conductive layer 215 c, the second conductive layer 213 b,and/or other conductive layers electrically connected to the first andsecond conductive layers may not be covered by the interlayer insulatinglayer 130 or the planarization layer 140, but may be electricallyconnected to one or more electronic devices or printed circuit boards.Accordingly, the first conductive layer 215 c, the second conductivelayer 213 b, and/or the other conductive layers electrically connectedto the first and second conductive layers may have portions that areelectrically connected to the one or more electronic devices or theprinted circuit boards. Here, the electrically connected portions needto be protected against external impurities such as moisture, and thus,the SNL 600 may also cover the electrically connected portions as aprotective layer. To do this, the SNL 600 may extend to, for example,the end of the substrate 100 of the display apparatus.

In some embodiments, in FIGS. 5 to 7, an upper surface of the SNL 600 ina direction toward the display area DA (e.g., along the −x direction)coincides with an upper surface of the polarization plate 520 (e.g., thesurface perpendicular or normal to the +z direction), but embodiments ofthe present disclosure are not limited thereto. For example, an end ofthe SNL 600 in the direction toward the display area DA (e.g., along the−x direction) may partially cover an upper surface at the edge of thepolarization plate 520. Otherwise, the end of the SNL 600 in thedirection toward the display area DA (e.g., along the −x direction) maynot contact the polarization plate 520 and/or the OCA 510.

The lower protective film 170 may be attached to correspond to the firstarea 1A (as shown in FIG. 7) in one or more suitable ways. For example,as shown in FIG. 9, which is a schematic plan view of a process inmanufacturing a display apparatus according to an embodiment of thepresent disclosure, the lower protective film 170 may be attached to thelower surface of the substrate 100 (e.g., the surface perpendicular ornormal to the −z direction), and in particular, the lower protectivefilm 170 may be applied to a lower surface of each of the display panelsso that the lower protective film 170 having a greater area than that ofthe first area 1A may be partially exposed to outside of the displaypanel (e.g., may partially extend past the edge of the display panel).In some embodiments, as shown in FIG. 10, an exposed part of the lowerprotective film 170 out of the display panel (e.g., past the substrate100), may be removed. Here, the exposed part of the lower protectivefilm 170 out of the display panel (e.g., past the substrate 100) may beremoved by irradiating the lower protective film 170 located around theedge of the substrate 100 with a laser beam.

When the lower protective film 170 is attached to the lower surface ofthe substrate 100, the lower protective film 170 having a width thatexactly corresponds to the width of the substrate 100 (e.g., along the+y direction) may be prepared and attached to the lower surface of thesubstrate 100 so as not to be exposed to outside of the substrate 100.However, in this case, the lower protective film 170 and the substrate100 have to (e.g., should) be exactly aligned (e.g., substantiallyaligned) with each other. In the method of manufacturing the displayapparatus according to embodiments of the present disclosure, the lowerprotective film 170 and the substrate 100 are aligned such that thelower protective film 170 does not overlap with the bent area BA, thelower protective film 170 is attached to the lower surface of thesubstrate 100, and after that, only the exposed part of the lowerprotective film 170 exposed outside of the substrate 100 is removed.Therefore, there is no need to exactly align (e.g., substantially align)the lower protective film 170 with respect to the substrate 100, andthus, the defect rate during manufacturing may be greatly reduced andthe time period taken to manufacture the display apparatus may beeffectively reduced.

In some embodiments, as shown in FIG. 9, a printed circuit board FPCBmay be attached to the display panel. The printed circuit board FPCB maybe attached after the plurality of display panels is obtained by cuttingthe mother substrate 100 and the temporary protective film 20 (as shownin FIG. 4), and before removing the temporary protective film 20. Forexample, the polarization plate 520 may be attached to the encapsulationlayer 400 via the OCA 510, and then the printed circuit board FPCB maybe attached to the display panel before applying the SNL 600. Theprinted circuit board FPCB may be attached to the second area 2A of thedisplay panel, and in this case, may be electrically connected to thesecond conductive layer 213 b.

Here, as shown in FIGS. 9 and 10, a length of the second area 2A in adirection crossing (e.g., perpendicular or normal to) a virtual straightline IL connecting a center C1 of the first area 1A and a center C2 ofthe second area 2A (e.g., along the +y direction) of the display panelmay be equal to a length of the printed circuit board FPCB in adirection crossing (e.g., perpendicular or normal to) the virtualstraight line IL (e.g., along the +y direction).

As described above, the lower protective film 170 is attached afterremoving the temporary protective film 20, and the lower protective film170 is not over or in the second area 2A, to which the printed circuitboard FPCB is attached. When the printed circuit board FPCB is attachedto the second area 2A after removal of the temporary protective film 20,the printed circuit board FPCB may not be attached (e.g., consistentlyattachable) to an exact location of the display panel due to theflexibility of the display panel. Therefore, the printed circuit boardFPCB may be attached to the second area 2A of the display panel beforeremoving the temporary protective film 20, and thus, the printed circuitboard FPCB may be attached to the second area 2A of the display panelwhile the display panel is supported by the temporary protective film 20to some degree.

Here, when the length of the second area 2A in the direction crossingthe virtual straight line IL (e.g., along the +y direction) of thedisplay panel is equal to the length of the printed circuit board FPCBin the direction crossing the virtual straight line IL (e.g., along the+y direction), deformation of the display panel after removal of thetemporary protective film 20 may be prevented or reduced. When thelength of the printed circuit board FPCB in the direction (e.g., alongthe +y direction) crossing the virtual straight line IL is less than thelength of the second area 2A in the direction crossing the virtualstraight line IL of the display panel (e.g., along the +y direction),only a part of the edge of the second area 2A extending in the directioncrossing the virtual straight line IL (e.g., along the +y direction)contacts the printed circuit board FPCB. In this case, since the entireedge of the second area 2A does not contact the printed circuit boardFPCB, the second area 2A may not be evenly supported by the printedcircuit board FPCB, and accordingly, the substrate 100 may be deformedat the second area 2A. However, when the length of the second area 2A inthe direction crossing the virtual straight line IL (e.g., along the +ydirection) of the display panel is equal to the length of the printedcircuit board FPCB in the direction crossing the virtual straight lineIL (e.g., along the +y direction), the entire edge of the second area 2Acontacts the printed circuit board FPCB, and the second area 2A isevenly supported by the printed circuit board FPCB. Accordingly, thepossibility of deformation of the substrate 100 at the second area 2Amay be greatly reduced.

When the printed circuit board FPCB does not directly contact thesubstrate 100, but the electronic chip EC contacts the substrate 100 andthe printed circuit board FPCB is electrically connected to theelectronic chip EC (as shown in FIG. 11), the length of the second area2A in the direction crossing the virtual straight line IL (e.g., alongthe +y direction) of the display panel may be equal to the length of theelectronic chip EC in the direction crossing the virtual straight lineIL (e.g., along the +y direction).

It has been described that the plurality of display units DU are formedon the mother substrate 100, and that the mother substrate 100 and thetemporary protective film 20 are simultaneously cut (e.g., at the sametime) to obtain the plurality of display panels, but embodiments of thepresent disclosure are not limited thereto. For example, as shown inFIG. 12, which is a schematic cross-sectional view of a process ofmanufacturing a display apparatus according to an embodiment of thepresent disclosure, the substrate 100 including a material havingflexible or bendable characteristics may be formed on the carriersubstrate 10, and then, one display unit DU may be formed on the firstarea 1A (e.g., as in FIG. 5) of the substrate 100. In some embodiments,as shown in FIG. 13, the substrate 100 is separated from the carriersubstrate 10, and then the temporary protective film 20 may be attachedto a lower surface of the substrate 100 (e.g., the surface perpendicularor normal to the −z direction).

In this case, the substrate 100 may initially include the first area 1A,the second area 2A, and the bent area BA between the first area 1A andthe second area 2A, and the temporary protective film 20 may be attachedto the lower surface of the substrate 100 throughout the first area 1A,the bent area BA, and the second area 2A (e.g., as in FIG. 5). FIG. 5shows a state in which the temporary protective film 20 is attached asdescribed above.

After that, the above descriptions with reference to FIGS. 5 to 8 may beapplied to the manufacturing processes. For example, as shown in FIG. 5,the polarization plate 520 may be attached, the printed circuit boardFPCB or the electronic chip EC may be electrically connected to thesecond conductive layer 213 b, and the SNL 600 may be formed. In someembodiments, as shown in FIG. 6, the temporary protective film 20 may beremoved, and then the lower protective film 170 may be attached to thelower surface of the substrate 100 to correspond to the first area 1A asshown in FIG. 7. In some embodiments, as shown in FIG. 8, the substrate100 may be bent around the bending axis BAX of the bent area BA tomanufacture the display apparatus.

In some embodiments, as described above with reference to FIGS. 9 and10, the lower protective film 170 may have an area greater than that ofthe first area 1A so that the lower protective film 170 is partiallyexposed to outside the substrate 100, and the lower protective film 170may be irradiated with a laser beam in order to remove the exposed partof the lower protective film 170. In some embodiments, as shown in FIGS.10 and 11, the length of the second area 2A in the direction crossingthe virtual straight line IL that connects the center C1 of the firstarea 1A and the center C2 of the second area 2A of the display panel(e.g., along the y direction) may be equal to the length of the printedcircuit board FPCB or the electronic chip EC in the direction crossingthe virtual straight line IL (e.g., along the y direction).

Methods of manufacturing the display apparatus are described above, butembodiments of the present disclosure are not limited thereto, and thedisplay apparatus manufactured by the method is also included in thescope of the present disclosure.

The display apparatus according to an embodiment of the presentdisclosure may include, for example, the substrate 100, the display unitDU, the lower protective film 170, and a support layer 700 as shown inFIG. 14.

The substrate 100 may include the bent area BA between the first area 1Aand the second area 2A as described above, and the bent area BA may bebent around the bending axis BAX. Accordingly, a part of the lowersurface of the first area 1A in the substrate 100 and at least a part ofthe lower surface of the second area 2A in the substrate 100 face eachother.

The display unit DU is on the upper surface of the substrate 100 withinthe first area 1A. The display unit DU may include the thin filmtransistor 210 and the display device 300 (as described above withreference to FIGS. 5 to 7), and moreover, the display unit DU mayfurther include the encapsulation layer 400, the OCA 510, and/or thepolarization plate 520.

The lower protective film 170 is on the lower surface of the substrate100 to correspond at least partially to the first area 1A. In someembodiments, the support layer 700 is between the lower protective film170 and the lower surface of the second area 2A in the substrate 100.The support layer 700 may include a metal (such as stainless steel)and/or a synthetic resin having elasticity. As described above, thelower protective film 170 may not exist in the bent area BA and thesecond area 2A. The support layer 700 may be attached to the lowerprotective film 170, and may also be attached to the lower surface ofthe second area 2A in the substrate 100. In some embodiments, additionallayers may be between the lower protective film 170 and the supportlayer 700.

The substrate 100 may be smoothly bent in the bent area BA (as shown inFIG. 14), and to do this, the substrate 100 needs to have a sufficientor suitable strength. However, when the substrate 100 has thissufficient strength, the substrate 100 may be damaged during bending.Therefore, the substrate 100 needs to have excellent flexibility orbending properties at least in the bent area BA. In this case, as shownin FIG. 15, which is a schematic cross-sectional view of part of adisplay apparatus according to an embodiment of the present disclosure,the substrate 100 may be deformed in the bent area BA.

In more detail, recognizing that a portion of the substrate 100 in thefirst area 1A where the support layer 700 is located has a first lowersurface 101 a, and a portion the substrate 100 in the second area 2Awhere the support layer 700 is located has a second lower surface 102 a,a distance d1 between the first lower surface 101 a and the second lowersurface 102 a may be less than a distance d2 between the parts of thefirst lower surface 101 a and the second lower surface 102 a facing eachother in the lower surface of the substrate 100 (e.g., at the edges ofthe bent area adjacent to areas 1A and 2A).

Since the lower protective film 170 is attached to the support layer 700in the first area 1A of the substrate 100 and the second lower surface102 a is attached to the support layer 700 in the second area 2A of thesubstrate 100, the distance d1 has a fixed value. However, using aseparate element for fixing the location of the bent area BA of thesubstrate 100, the bent area BA may be transformed by a recovery forcethat may recover the substrate 100 to a status before the substrate 100is bent. Accordingly, the maximum distance d2 between the facingportions of the substrate 100 in a part of the substrate 100 between thefirst lower surface 101 a and the second lower surface 102 a may begreater than the distance d1 between the first lower surface 101 a andthe second lower surface 102 a.

In this case, a first virtual plane including the upper surface of thesubstrate 100 corresponding to the support layer 700 within the secondarea 2A may be taken into account. The first virtual plane may beparallel to the x-y plane. Here, as shown in FIG. 15, a part of theupper surface of the substrate 100 between a first upper surface of thefirst area 1A of the substrate 100 corresponding to the support layer700 and a second upper surface of the second area 2A of the substrate100 corresponding to the support layer 700 may protrude past the firstvirtual plane in a direction opposite to the direction toward thedisplay unit DU (e.g., along the −z direction). For example, thesubstrate 100 may be downwardly convex (e.g., perpendicular or normal tothe −z direction) at the bent area BA adjacent to the second area 2A.

The part of the bent area BA adjacent to the first area 1A may bedirectly and/or indirectly supported by the first area 1A that is largein area, whereas the part of the bent area BA adjacent to the secondarea 2A may be directly and/or indirectly supported by the second area2A that is relatively small in area. Accordingly, the substrate 100 maybe downwardly convex (e.g., perpendicular or normal to the −z direction)at the bent area BA adjacent to the second area 2A.

Moreover, as shown in FIG. 16, which is a schematic cross-sectional viewof a part of a display apparatus according to an embodiment of thepresent disclosure, another part of the upper surface of the substrate100 between the first upper surface and the second upper surface mayprotrude past a second virtual plane in a direction toward the displayunit DU (e.g., along the +z direction), wherein the second virtual planemay be parallel to the x-y plane and may include the upper surface ofthe substrate 100 corresponding to where the surface the display unit DUis formed.

FIG. 17 is a schematic cross-sectional view of a part of a displayapparatus according to an embodiment of the present disclosure. In thedisplay apparatus according to the embodiment of the present disclosure,the support layer 700 includes a surface 701 in a direction toward(e.g., directly facing) the lower protective film 170 and a surface 702in a direction toward (e.g., directly facing) the second area 2A of thesubstrate 100, wherein the surface 701 and the surface 702 have areasthat are different from each other. In more detail, the surface 701 ofthe support layer 700 facing the lower protective film 170 may have agreater area than the surface 702 of the support layer 700 facing thesecond area 2A of the substrate 100.

In this case, the substrate 100 between the first area 1A in thesubstrate 100 corresponding to the support layer 700 and the second area2A in the substrate 100 corresponding to the support layer 700 mayprotrude past the first virtual plane in the direction opposite thedisplay unit DU (e.g., along the −z direction). For example, thesubstrate 100 may be downwardly convex (e.g., along the −z direction) inthe bent area BA adjacent to the second area 2A. However, protrusion ofthe substrate 100 in the direction toward the display unit DU (e.g.,along the +z direction) in the bent area BA adjacent to the first area1A may be prevented or reduced. When the area of the surface 701 of thesupport layer 700 facing the lower protective film 170 is greater thanthe area of the surface 702 of the support layer 700 facing the secondarea 2A of the substrate 100, deformation of the bent area BA adjacentto the first area 1A may be prevented or reduced.

FIG. 18 is a schematic cross-sectional view of a part of a displayapparatus according to an embodiment of the present disclosure. As shownin FIG. 18, the display apparatus according to the embodiment of thepresent disclosure further includes an electronic device 800 on thesecond upper surface of the substrate 100 in the second area 2Acorresponding to the support layer 700. The electronic device 800 mayinclude an integrated circuit for controlling electric signals that areto be applied to the display unit DU and/or an integrated circuit forreceiving electric signals from outside and converting the electricsignals to the electric signals to be applied to the display unit DU.

The display apparatus according to the embodiment of the presentdisclosure may include a reinforcing film 810 on the second uppersurface adjacent to the electronic device 800. The reinforcing film 810may prevent or reduce deformation of the substrate 100, which may occurin the second area 2A. Since the second area 2A in the substrate 100corresponds to the edge of the substrate 100 as shown in FIG. 18, thesecond area 2A may be deformed. However, when the reinforcing film 810is on the second area 2A, the deformation of the second area 2A may beeffectively prevented or reduced. Moreover, in order to increase thedeformation prevention or reduction effect, the reinforcing film 810 maycover all or substantially all of the exposed part of the second uppersurface around the electronic device 800. In some embodiments, the SNL600 shown in FIG. 7 may extend to the edge of the substrate 100 so as toat least partially cover the reinforcing film 810.

According to one or more embodiments of the present disclosure, themethod of manufacturing the display apparatus and the display apparatuscapable of reducing the defect rate during manufacturing while reducingmanufacturing costs may be implemented. However, the scope of thepresent disclosure is not limited by the above effects.

It should be understood that embodiments described herein should beconsidered in a descriptive sense only and not for purposes oflimitation. Descriptions of features or aspects within each embodimentshould typically be considered as being available for other similarfeatures or aspects in other embodiments.

As used herein, the terms “use”, “using”, and “used” may be consideredsynonymous with the terms “utilize”, “utilizing”, and “utilized”,respectively. Further, the use of “may” when describing embodiments ofthe present disclosure refers to “one or more embodiments of the presentdisclosure”.

As used herein, the terms “substantially”, “about”, and similar termsare used as terms of approximation and not as terms of degree, and areintended to account for the inherent deviations in measured orcalculated values that would be recognized by those of ordinary skill inthe art.

Also, any numerical range recited herein is intended to include allsubranges of the same numerical precision subsumed within the recitedrange. For example, a range of “1.0 to 10.0” is intended to include allsubranges between (and including) the recited minimum value of 1.0 andthe recited maximum value of 10.0, that is, having a minimum value equalto or greater than 1.0 and a maximum value equal to or less than 10.0,such as, for example, 2.4 to 7.6. Any maximum numerical limitationrecited herein is intended to include all lower numerical limitationssubsumed therein and any minimum numerical limitation recited in thisspecification is intended to include all higher numerical limitationssubsumed therein. Accordingly, Applicant reserves the right to amendthis specification, including the claims, to expressly recite anysub-range subsumed within the ranges expressly recited herein.

While one or more embodiments have been described with reference to thedrawings, it will be understood by those of ordinary skill in the artthat various changes in form and details may be made therein withoutdeparting from the spirit and scope as defined by the following claimsand equivalents thereof.

What is claimed is:
 1. A display apparatus comprising: a substratehaving an upper surface and a lower surface and comprising a bent areabetween a first area and a second area, the lower surface of thesubstrate in the first area and the lower surface of the substrate inthe second area at least partially facing each other; a display unitover the upper surface of the substrate in the first area; a lowerprotective film over the lower surface of the substrate in at least apart of the first area; a support layer between the lower protectivefilm in the first area and the lower surface of the substrate in thesecond area; and a reinforcing film over the upper surface of thesubstrate in the second area and not over the lower surface of thesubstrate in the first area and the bent area, wherein a first surfaceof the support layer is adhered to the lower protective film in thefirst area, and a second surface of the support layer opposite the firstsurface is directly adhered to the lower surface of the substrate in thesecond area without the lower protective film.
 2. The display apparatusof claim 1, wherein a part of the upper surface of the substrate in thebent area protrudes past a first virtual plane including the uppersurface of the substrate where the display unit is located within thefirst area, in a direction toward the display unit.
 3. The displayapparatus of claim 1, wherein a distance between the lower surface ofthe substrate in the first area where the support layer is located andthe lower surface of the substrate in the second area where the supportlayer is located is less than a maximum distance between facing portionsof the lower surface of the substrate in the bent area.
 4. The displayapparatus of claim 3, wherein a part of the upper surface of thesubstrate in the bent area protrudes past a second virtual planeincluding the upper surface of the substrate where the support layer islocated within the second area, in a direction away from the displayunit.
 5. The display apparatus of claim 1, wherein the first surface ofthe support layer adhered to the lower protective film in the first areahas an area that is different from an area of the second surface of thesupport layer directly adhered to the lower surface of the substrate inthe second area.
 6. The display apparatus of claim 1, wherein the firstsurface of the support layer adhered to the lower protective film in thefirst area has an area that is greater than an area of the secondsurface of the support layer directly adhered to the lower surface ofthe substrate in the second area.
 7. The display apparatus of claim 1,further comprising: an electronic device on a portion of the uppersurface of the substrate in the second area where the support layer islocated.
 8. The display apparatus of claim 7, wherein the reinforcingfilm covers all of an exposed part of the upper surface of the substratein the second area around the electronic device.
 9. The displayapparatus of claim 1, further comprising: an adhesive between the uppersurface of the substrate in the first area and the first surface of thesupport layer.
 10. A display apparatus comprising: a substrate having anupper surface and a lower surface and comprising a bent area between afirst area and a second area, the lower surface of the substrate in thefirst area and the lower surface of the substrate in the second area atleast partially facing each other; a display unit over the upper surfaceof the substrate in the first area; a lower protective film over thelower surface of the substrate in at least a part of the first area; asupport layer between the lower protective film in the first area andthe lower surface of the substrate in the second area; an inorganicinsulating layer extending from the display unit, the inorganicinsulating layer being arranged over the upper surface of the substratein the first area and the upper surface of the substrate in the secondarea, and having an opening not to be arranged in the bent area; and anorganic material layer covering the opening, wherein a first surface ofthe support layer is adhered to the lower protective film in the firstarea, and a second surface of the support layer opposite the firstsurface is directly adhered to the lower surface of the substrate in thesecond area without the lower protective film.
 11. The display apparatusof claim 10, wherein organic material layer includes an uneven surface.12. The display apparatus of claim 10, further comprising: a firstconductive layer on the organic material layer, the first conductivelayer extending from the first area toward the second area through thebent area.
 13. The display apparatus of claim 10, further comprising: astress neutralization layer over the organic material layer.
 14. Thedisplay apparatus of claim 10, further comprising: a reinforcing filmover the upper surface of the substrate in the second area and not overthe lower surface of the substrate in the first area and the bent area.15. The display apparatus of claim 10, wherein a part of the uppersurface of the substrate in the bent area protrudes past a first virtualplane including the upper surface of the substrate where the displayunit is located within the first area, in a direction toward the displayunit.
 16. The display apparatus of claim 10, wherein a distance betweenthe lower surface of the substrate in the first area where the supportlayer is located and the lower surface of the substrate in the secondarea where the support layer is located is less than a maximum distancebetween facing portions of the lower surface of the substrate in thebent area.
 17. The display apparatus of claim 16, wherein a part of theupper surface of the substrate in the bent area protrudes past a secondvirtual plane including the upper surface of the substrate where thesupport layer is located within the second area, in a direction awayfrom the display unit.
 18. The display apparatus of claim 10, whereinthe first surface of the support layer adhered to the lower protectivefilm in the first area has an area that is different from an area of thesecond surface of the support layer directly adhered to the lowersurface of the substrate in the second area.
 19. The display apparatusof claim 10, wherein the first surface of the support layer adhered tothe lower protective film in the first area has an area that is greaterthan an area of the second surface of the support layer directly adheredto the lower surface of the substrate in the second area.
 20. Thedisplay apparatus of claim 14, further comprising: an electronic deviceon a portion of the upper surface of the substrate in the second areawhere the support layer is located.
 21. The display apparatus of claim20, wherein the reinforcing film covers all of an exposed part of theupper surface of the substrate in the second area around the electronicdevice.
 22. The display apparatus of claim 10, further comprising: anadhesive between the upper surface of the substrate in the first areaand the first surface of the support layer.